Replay Capture Suite (Shareware/Windows) Best value package!!!
Record and convert any audio/video stream including streaming Windows Media, Real Audio/Video, Nullsoft Video, Flash Video (including YouTube and Google Videos), online Sirius and XM Radio, any music from Web Radio Stations and Music Subscription services, and much more!

Streaming audio recording/ripping software

Replay Music (Shareware/Windows) Editor's choice!Record any web radio station or streaming music service. Get perfectly separated high quality MP3 files, automatically tagged with the artist and song title.

RadioTracker (Shareware/Windows) Editor's choice IceCast/ShoutCast stream ripper that can split and tag songs automatically. Allows to record the music you've selected in MP3 format as soon as it is played on any of over 14,000 watched internet radio stations worldwide.

Freecorder 8 (Freeware / IE and Firefox)
Free audio recorder that can record any sound produced by your sound card (Freeware / Windows ) even if you don't have Stereo Mix / Wave-Out Mix / What U Hear in Windows 7/Vista/XP

Audacity (Freeware / Windows, Linux, MacOSX) Editor's choiceFree audio editor that can record any sound produced by your sound card.